System and method for installing solar panels

ABSTRACT

A solar panel system for determining how many solar panels connected to a controller is provided. An electrical pathway connects the controller to at least one solar panel. A first resistance is associated with each of the at least one solar panel. An external environment resistance is defined by a cumulative presence of at least the first resistance associated with each of the at least one solar panel, wherein the external environment resistance is different based on a total number of the at least one solar panels connected to the electrical pathway. A second resistance is associated with the controller. The external environment resistance and the second resistance at least partially define a voltage divider to receive an input voltage and produce an output voltage. The controller is programmed to determine from the produced output voltage the total number of the at least one solar panel connected to the controller along the electrical pathway.

CROSS REFERENCE TO RELATED APPLICATIONS

The instant application is a continuation-in-part and claims priority toU.S. Ser. No. 13/964,485 filed on Aug. 12, 2013, is acontinuation-in-part and claims priority to U.S. Ser. No. 13/927,776filed Jun. 26, 2013, both entitled System and Method for InstallingSolar Panels, the contents of which are expressly incorporated herein intheir entireties.

FIELD OF THE INVENTION

The various embodiments described herein relate generally to theinstallation of solar panels. More specifically, the instant applicationrelates to a methodology for installing solar panels that minimizes oreliminates the need for specialized training or knowledge in electricalpower systems.

BACKGROUND

Solar technology presents a viable green source of energy as analternative to fossil fuels. This is particularly the case forgeographic areas that have a high amount of daylight and/or higher thanaverage fuel costs, such as Hawaii.

An ongoing obstacle to the adoption of solar panels as a home energysolution remains the expense, particularly in the purchase of thecomponents and the installation. A typical residential solar system,will include a number of solar panels connected by electrical cables toa junction box. The output of the junction box is then fed to loaddistribution center for internal use. Electrical cable between the solarpanels and the junction box are cut to length, and spliced ends of thewires are connected to terminals using generally known methodologiesfamiliar to the field of electricians.

A drawback of the above system is that the total maximum output of thepanels must not exceed the capacity of the home's existing electricalservice, in that having an output in excess of capacity can damage thesystem and/or present a safety hazard. However, different solar panelshave different outputs and different homes have different capacities.The underlying calculations on the appropriate number of panels aregenerally known by electricians and professional solar panel installers,but are not typically known by a typical consumer. Many consumers arealso not familiar with how to make safe electrical grade connectionsbetween components and/or lack the tools to do so. Jurisdictions thusoften require professional installers to install solar panel systems toensure safe and proper installation, which adds to the overallinstallation costs. In general, any wired in place solar or electricalsystem must be installed by a licensed electrical contractor.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments in accordance with the present disclosure will bedescribed with reference to the drawings, in which:

FIG. 1 illustrates an environment of an embodiment of the invention.

FIG. 2 illustrates a solar panel according to an embodiment of theinvention.

FIG. 3 illustrates a cable connecting to various components according toan embodiment of the invention.

FIG. 4 illustrates a table of possible shapes of connectors based onsystem capacity according to an embodiment of the invention.

FIG. 5 illustrates an embodiment of a smart station.

FIG. 6 illustrates a flowchart of the operation of a smart stationaccording to an embodiment of the invention.

FIG. 7 illustrates a more detailed end-to-end embodiment of theinvention.

FIG. 8 illustrates a data store and accompanying components according toan embodiment of the invention.

FIG. 9 illustrates another embodiment of the invention.

FIG. 10 illustrates another embodiment of the invention.

FIG. 11 illustrates another embodiment of the invention.

FIG. 12 is a conceptual drawing of an equivalent circuit created bycomponents of an embodiment of the invention to facilitate counting thenumber of panels.

FIGS. 13A-C show an embodiment of a solar panel with associated cablingfor a series connection.

FIG. 14 shows an embodiment of internal connections for the embodimentof FIGS. 13A-C.

FIG. 15 is a conceptual drawing of an equivalent circuit created bycomponents of an embodiment of the invention to facilitate counting thenumber of panels in a series connection.

FIGS. 16A and 16B illustrate the embodiment of FIG. 15 with a missingend cap.

FIG. 17 illustrates the embodiment of FIG. 15 with a break in theelectrical pathway.

FIGS. 18A-C show different embodiment of resistor placement in theembodiment of FIG. 15.

FIG. 19 shows an embodiment of internal connections for the embodimentof FIGS. 13A-C with a resistor for the end cap.

FIGS. 20A-C show an embodiment of a solar panel with associated cablingfor a parallel connection.

FIG. 21 shows an embodiment of internal connections for the embodimentof FIGS. 20A-C.

FIG. 22 illustrates an embodiment of resistor placement in theembodiment of FIG. 21.

FIG. 22 illustrates another embodiment of resistor placement in theembodiment of FIG. 21.

FIG. 24 illustrates the embodiment of FIG. 22 with an end cap.

FIG. 25 illustrates the embodiment of FIG. 21 with a break in theelectrical pathway.

FIG. 27 illustrates a flowchart of another embodiment of the inventionrelating to capacitive current draw based counting.

FIG. 28 illustrates a flowchart of another embodiment of the inventionrelating to startup of the smart station.

FIG. 29 illustrates another embodiment of the invention of a daisy chainconnection of modules.

FIG. 30 illustrates another embodiment of the invention of a trunkbranch connection of modules.

DETAILED DESCRIPTION

In the following description, various embodiments will be illustrated byway of example and not by way of limitation in the Figures of theaccompanying drawings. References to various embodiments in thisdisclosure are not necessarily to the same embodiment, and suchreferences mean at least one. While specific implementations and otherdetails are discussed, it is to be understood that this is done forillustrative purposes only. A person skilled in the relevant art willrecognize that other components and configurations may be used withoutdeparting from the scope and spirit of the claimed subject matter.

Because of safety concerns, any wired in place solar or electricalsystem is typically installed by a licensed electrical contractor.Embodiments herein provide methodologies and architecture that addressthose safety concerns. Embodiment herein can thus reduce or eliminatethe need for onsite engineering and allow anyone to safely connect andinstall a solar panel system.

Embodiments of the invention herein provide a “plug and play” solarpanel installation methodology that requires little or no reliance onprofessional electricians or installers. End consumers can thus installthe systems on their own, thereby reducing the overall installationcosts.

Referring now to FIG. 1, an embodiment of a deployed solar panel systemis shown. Solar panels 102 are an originating source of electricalpower. Each panel 102 includes an interface adaptor 104 that connects tobranches of a cable 106. Cable 106 also connects to smart station 108(which may be generically considered a system controller), discussed inmore detail below. Smart station 108 in turn connects to a home loadcenter 110 through a connector 109. Home load center 110 in turnconnects to a utility meter 112 and/or other electrical leads 114.

Referring now to FIG. 2, an embodiment of solar panel 102 and adaptor104 is shown (not to scale—panel 102 would typically be considerablylarger). Adaptor 104 is preferably the only electrical conduit throughwhich power from panel 102 is sent downstream. Adaptor 104 is alsopreferably mounted to or otherwise integral with panel 102.

Referring now to FIG. 3, an embodiment of adaptor 104 relative to cable106 is shown. Adaptor 104 may include a data source 302. Data source 302is preferably a programmed integrated circuit, but this need not be thecase and data source 302 may be any other form of hardware and/orsoftware data source. The invention is not limited to any physicalembodiment of data source 302.

Data source 302 preferably includes information about the solar panel102 to which data source 302 is connected, such information being storedor generated on an as needed basis. Such information may include therated wattage of the solar panel 102 that data source 302 is associatedwith. In addition and/or the alternative, such information may includean identifier or marker. Such information may also contain otheridentification information that may be of use, such as the manufacturer,although such information may not be necessary for operation of theembodiment. The invention is not limited to any particular type of datastored and/or generated by data source 302, or the format of such data.Data source 302 may receive power from the panel 102 directly, through alocal battery, or via feedback from smart station 108 or otherdownstream elements. Data source 302 may also be a passive device thatrequires no independent power, but which can impart its information bymodulating other signals that react therewith.

Adaptor 104 also preferably includes a connector 304 with various pinsand/or slots configured to mate with a corresponding branch connector306 of cable 106. The various pathways provided by the pins and/or slotswill be appropriate to convey power from panels 102 to smart station108, as well as the requisite information from data source 302.

The shape of the connectors 304/306 may have various generic or uniquefeatures. At a minimum, each connector combination 304/306 is preferablyof a plug in type, i.e., connector 306 can mate with connector 304 bysimply physical contact or insertion, and without the need to strip anywires. This provides a “plug and play” feature that allows installationwithout specific knowledge of safely stripping and connecting electricalcable with electrical terminals.

Connectors 306 may be at preset positions along cable 106. In thealternative, connectors 306 may be snap on components that the consumercan connect to the cable during installation at desired customizedpositions.

The shape and configuration of connectors 304/306 could be universal toany particular solar panel 102 with adaptor 104. In the alternative thecombination could be unique to panels of common rated outputs. By way ofnon-limiting example, a square arrangement of connectors 304/306 couldbe used for a panel rated for 50 watts, while a triangular arrangementcould be for panels of 100 watts. The number of branch connectors 306 incombination with the unique shape of the connectors can collectivelylimit the total output of an array of panels 102 to smart station 108.By way of non-limiting example, a cable 106 with sixteen (16) branchpoints with connectors 306 having a shape specific to 200 watt panels102 would have a maximum limit of 3.2 kW, and could be used safely withsystems that could handle such capacity. Not every connector 306 need beconnected to panels, and unused connectors 306 are preferably covered bya weather resistant cap.

Cable 106 also includes a connector 310 at the end that connects tosmart station 108, which has a mating connector or conduit 312. At aminimum, each connector combination 310/312 is preferably of a plug intype, i.e., connector 310 can mate with connector 312 by simple physicalcontact or insertion, and without the need to strip any wires. Thisprovides a “plug and play” feature that allows installation withoutspecific knowledge of how to safely strip and connect electrical cablewith electrical terminals.

Cable 106 may also include an equipment-grounding conductor as well asoptional grounding electrode conductor. The equipment ground conductorwould connect to the equipment ground that comes out of the module, andwould ultimately be grounded through the grounding of the home'sexisting electrical system. The grounding electrode conductor would beconnected to a separate ground connection and will ultimately begrounded through a separate grounding rod not attached to the home'sexisting electrical service.

The shape and configuration of connectors 310/312 could be universal toany smart station 108. In the alternative, connector combination 310/312is preferably unique to the system size as dictated by the smart station108. By way of non-limiting example, a trapezoid arrangement could beused for a system rated for 3.8 kilowatts, while a hexagon could be forsystems of 13.4 kilowatts. FIG. 4 shows a table 400 of non-limitingexamples of different connector configurations for different systemratings. The invention is not limited to any particular design or systemsize. The only guiding principles are that preferably (1) differentsystem sizes have different shaped connectors 310/312, and (2)connectors 310/312 have different shapes than connectors 304/306 thatconnect panels 102 and cable 106. In addition and/or alternative todifferent shapes, different colors could also be used.

The number of branched connectors 306 in combination with a uniqueconnection mechanism collectively limit the total output of an array ofpanels 102 to smart station 108. By way of non-limiting example, a cable104 with sixteen (16) branch points with connectors 306 specific to 200watt panels 102 would have a maximum limit of 3.2 kW, and could be usedsafely with systems that could handle such capacity.

As shown in FIG. 5, smart station 108 may have multiple connectors 312to connect to multiple cables 106. Three are shown in FIG. 5, but theremay be any number of connectors 312 (including only a single connector312) as appropriate for the system. Each of the connectors 312preferably has the same structure; along with the specific cables 106,this would ensure that each connector 312 connects to the same maximumarray of panels 102. However, this need not be the case, and differentconnectors 312 may be used. The total number of connectors 312 ispreferably system specific, e.g., if a smart station 108 can handle 60panels of a certain type, then three connectors 312 configured to matewith cables 106 that support 20 panels of that type may be appropriate.However, this need not be the case, and there may be more connectors312.

Alternatively, smart station 108 might have connectors 312 of differenttypes/structures. The smart station would allow the user to select justone, or an appropriate subset, of the multiple connectors 312. Selectinga single connector 312 or an appropriate subset of connectors 312 wouldpreferably disable the other connectors 312. This potentially allows auniversal smart station 108 that could be used safely for differentsystem sizes.

Referring now to FIG. 5, a schematic of various control elements ofsmart station 108 is shown. The smart station 108 has at least oneconnector 312 to connect to different cables 106 as appropriate.Connectors 312 preferably connect to connector 109 through a powerpathway 520; connector 109 ultimately connects to the home load center110 through a regulation component 524 to deliver power from the arrayof solar panels 102 for end use. Connector 109 preferably also has aunique shape that is matched to the system, but this need not be thecase, and may represent conventional electrical leads. A ground 526 alsoconnects to power pathway 520 via ground pathway 526 for groundingpurposes as discussed herein. Connector 109 can also act as the groundpath via the homes load center 110.

Smart station 108 also may include a controller 502, a communicationsmodule 506, and a display 504. Controller 502 may include a processor508 and a memory 510. The various components may be any combination ofelectronic computer hardware and/or software as needed to effectuate thefunctionality of smart station 108 as discussed herein. The components,which may be integral or distinct, are connected using knownmethodologies and are not discussed further herein.

As noted above, cable 106 includes structure to carry informationsignals from the data sources 302 in the panels 102. These signals reachcontroller 502 via a signal pathway 522. As discussed in more detailbelow, controller 502 analyzes the signals and may enable or disable thesystem based upon system status. Signal pathway 522 is shown as abidirectional pathway, but it may be unidirectional.

Controller 502 may be programmed with certain maximum/minimum parametersof the system. For example, controller 502 may be programmed with amaximum number of panels 102 and/or maximum amount of wattage that thesystem can support. Controller 502 may also be in communication with thedata sources 302 of the panels 102. Since the data source 302 mayinclude information about the corresponding panel 102, system controller502 can determine whether the complete system connections are within themaximum parameters, and disable the system when this is not the case.For example, system controller 502 can determine whether too many panels102 are connected, or whether the total rated wattage of the connectedpanels 102 exceed what the system can handle. Controller 502 can alsomonitor the presence of ground fault errors, loss of groundingcontinuity, over-current and/or over-voltage. These are exemplary only,and the invention is not limited to any particular system parameter(s)that controller 502 monitors and/or reacts to.

Regulator element 524 can be used for system control. Regulator 524 maybe a simple switch under control from controller 502. Controller 502 canthus enable or disable the flow of power through smart station 108.Alternatively, controller 502 could instruct panel 102 to shutdown viadata source 302. The structure of such components are known to those ofskill and not further detailed herein.

Controller 502 also may be programmed to monitor the output current ofthe array of panels 102. As discussed below, it is possible for thearray of panels 102 to generate higher output than system capacity. Insuch a case, controller 502 could disable the system, or otherwisegovern the output fed to home load center 110 back to within acceptablelevels. In theory some element would need to monitor this collectivepower flow for controller 502 to make the appropriate decision;regulator element 524 could by way of non-limiting example include anammeter that monitors the collective power flow and informs controller502.

Controller 502 could also attempt to rectify the problem by altering theelectrical layout of the system. For example, control 502 could shutdown one or more of connectors 312. In another example, control 502could instruct one or more adaptors 104 to disconnect or reduce thepower flow from their corresponding panels 102; selective deactivationof adaptors 104 may identify a “problem” panel 102. In addition and/orthe alternative, adaptors 104 could monitor the flow of electricity ofthe panel and on its own authority shut down the power connection if theoutput of the panel exceeds the rated wattage. Such intelligentcapability may also be incorporated in the same integrated circuitry ofadaptor 104 that supports data source 302.

Referring now to FIG. 6, a flowchart of an example of a methodology forcontroller 502 is shown. At step 600, the system starts and initializes.As part of this initialization, the continuity of the equipmentgrounding conductor between smart station 108 and panels 102 may betested. At step 602, controller 502 detects whether or not at least onepanel is connected to the system; such detection may be via informationof the data sources 302 of an attached panel 102, or the simpledetection of a power output from a panel 102. If no panel is connected,the user is prompted at step 604 to attach additional panels, andcontrol returns to step 602; this cycle loops until a panel is detected,at which point control passes to step 606. The prompt at 604 may be viadisplay 504, or a signal sent through communications module 506 to aremote device. In another embodiment, steps 602 could be configured todetermine if a pre-set number of panels 102 have been reached, andprompts the user to add panels until that number is achieved.

At step 606, controller 502 confirms that the connected panels 102 arewithin the operating system parameter(s). The controller 502 preferablydetermines this based on the information from the connected data sources302 relative to a stored threshold, which may be a data table. Forexample, if the parameter is a number of panels, then controller 502counts the number of data sources 302 that it receives signals from(this may be a direct count, or an indirect count based on data takenfrom the information received from the data sources 302). If theparameter is the total rated wattage, then controller 502 adds the ratedwattages of the panels as received from data sources 302. Theseaccumulated value(s) are then compared against the threshold as stored.If the value(s) are within acceptable limits, then the user is promptedat step 608 that the system can be enabled. If one or more of the valuesare not within acceptable limits (e.g., there are too many panels,and/or the total rated wattage is above system capacity), then thesystem is disabled at step 612 and the user is prompted of the nature ofthe problem at step 614. Additional checks may also be occurring forsystem abnormalities, e.g., grounding fault, over-voltage, over-current,etc.

Steps 606 and 608 continue in a loop until the user activates the systemat 610; this gives the user the opportunity to add more panels while thesystem monitors changes to confirm that the installation remains withinsystem parameters. Once the user engages the system at 610 (which inFIG. 6 only occurs if the system is not exceeding some value at 606),normal system operation engages at step 611.

During normal system operation, controller 502 continues to monitor thestatus of the data sources 302 for changes in the connected panels 102,and potentially other system abnormalities. If a configuration changeoccurs that exceeds system parameter(s) at step 616, then controller 502disables or governors the system at step 612 as discussed above.

Optionally, the system can as a fallback at step 618 determine whetherthe total output of the array of panels 102 exceeds a safety level; thissafety level could be the same threshold as used for the total ratedwattage, or some other value. If such an excess is detected, controller502 disables or governors the system at 612. In the alternative, control502 can communicate with the adaptors 104 to shut down individualpanels.

Referring now to FIG. 7, a more detailed schematic of a system 700according to an embodiment of the invention is shown.

As noted above, it is possible that overages can occur despite the abovesafety measures. One such reason is simple mechanical failure. Anothersuch reason would be if the user defies the instructions and connectsmultiple panels 102 in series or parallel through connections other thanadaptor 104, referred to herein as a “cluster” of panels. Yet anotherwould be if a user damaged the system by cutting and splicing wirestogether. In such a case the information from data store 302, which isspecific to a particular panel, would not accurately represent thenumber of panels or the output characteristics of the cluster.

There are a variety of methodologies to prevent the formation ofclusters. One such methodology is to exclude connectors on panels 102other than adaptor 104 bearing specific connectors 304. Anothermethodology for when other connections are present is to physically orelectrically disable such other connections when adaptor 104 is used.For example, insertion of connector 306 into 304 physically flips aswitch that disconnects other connectors. By way of another example,adaptor 104 includes a cap that may be inserted into other connectorsinherent to panel 102.

Referring now to FIG. 8, a schematic of an embodiment of data store 302on adaptor 104 relative to panel 102 is shown. At a minimum, data storepreferably includes a memory 802 with the information about panel 102.Memory 802 can communicate with cable 106 via a signal pathway 804 thatterminates in connector 304.

If “smart” functions are desired, a processor 806 may also be provided.One optional smart function is for processor 806 to control power outputfrom panel 102 via switch 810 on power lines 808. Another optional smartfunction is for processor 806 to control other power connections 812 viaa switch 814. As noted above, data store 302 can, either on its owncontrol or under instruction from smart station 108, enable and disablethe various power conduits to prevent daisy chaining and/or to isolatepotential problem areas.

According to another embodiment of the invention, the functionality ofsmart station 108 can be separated into distinct components, which mayhave distinct or overlapping functionality. By way of non-limitingexample, FIG. 9 shows smart combiner 402 that connects to a station 404.Smart combiner 402 may be mounted on the roof or otherwise in closeproximity of the panels 102; the racking (not shown) for the array ofsolar panels 102 may be an appropriate attachment structure. The closerproximity allows for shorter cables 106, as cables 106 do not need torun the full length to the station 404. A single cable/connection 406can then connect smart combiner 402 and smart station 404.

The cable 106 will feed into the smart combiner 402 via connectors 312consistent with the description of FIG. 1. Smart combiner 402 may havecomponents similar to those discussed with respect to FIG. 5 to monitorand react to system parameters. This will give the user real-timefeedback (such as LED lights) regarding connections about how manypanels 102 can be safely connected as the user is connecting panels onthe roof. The smart combiner box may also ground the panels and rackingsystem by biting into the racking. In this embodiment, other functionsof the smart station 108 of FIG. 1—including shutting off the power orreducing power produced by the solar panels, cutting off the flow ofpower into the home's electrical system, recognizing ground faults,over-voltage, and over-current situations, etc.—would be part of station404. Smart combiner 402 and station 404 could be connected by custom endcables in the manner discussed herein, or more conventional electricalwiring. Smart combiner 402 could serve a grounding function by clippingdirectly on to the racking for the panels. The smart combiner 402 couldground the racking by running a grounding wire back through the cablefrom the smart connector to the smart station 108.

The various system monitoring and diagnostics of the embodiment of FIG.9 preferably run according to the same flowchart as shown in FIG. 6.However, the functionality of controller 502 in the decision making canbe implemented in smart combiner 402 and/or station 404. If bothcombiner 402 and station 404 have controllers, the two may consult witheach other (which may be as simple as exchanging data) to determinewhether the system is operating within safe parameters and/or whetheract needs to be taken.

Solar panels 102 preferably include a DC/AC inverter to output AC power,such as AC solar panels, sometimes referred to as AC modules. An ACmodule is defined in relevant part by NEC 690.2 as “a complete,environmentally protected unit consistent of solar cells, optimizers,inverters, and other components . . . designed to generate ac power whenexposed to sunlight.” When used in conjunction with AC modules, cables106 would be at least partially AC power cables. A charge converterand/or batteries (not shown) could also be provided.

The distribution of components and functionality in connection herein isnot limited to FIG. 9; so long as the desired functionality (which mayinclude some, all, and/or additional functionality that discussedherein) is implemented, the physical placements of the components maynot be relevant. Other distributions, or combinations of distributionsare thus possible. Controllers and processors may thus be individualcomponents located in particular components, or distributed in multiplecomponents that cooperate to execute the functionality discussed herein.

By way non-limiting example, FIG. 10 shows an embodiment in which thefunctionality of smart combiner 402 and/or station 404 is incorporatedinto a DC/AC inverter 1002 that connects to one or more panels 102. Tothe extent not already present in a conventional DC/AC inverter,inverter 1002 would include the necessary hardware and/or software toeffectuate the functionality as consistent with smart combiner 402and/or station 404 above. Cable connections between componentspreferably retain their unique characteristics as discussed herein.

By way of another non-limiting example, so-called“micro-inverters”—which provide DC/AC conversion on a panel-per-panelbasis—can also be used to provide the functionality as discussed herein.FIG. 11 shows an embodiment in which the functionality of smart combiner402 and/or station 404 is incorporated into a micro DC/AC inverter 1102that connects to (or is incorporated into) one or more panels 102. (Onlyone such panel/inverter combination is shown in FIG. 11, although it isto be understood any number of panel/inventor combinations could bepresent.) To the extent not already present in a conventional microDC/AC inverter, inverter 1102 would include the necessary hardwareand/or software to effectuate the functionality as consistent with smartcombiner 402 and/or station 404 above. Cable connections betweencomponents preferably retain their unique characteristics as discussedherein.

By way of another non-limiting example, the functionality smart combiner402 and/or station 404 can be incorporated into data store 302 asdiscussed with respect to FIG. 8.

The various connectors herein are described as single/unitaryconnectors. However, this need not be the case, and the connectors couldhave multiple branches, e.g., one or more branches for powertransmission, one or more branches for grounding purposes, and/or one ormore branches for information transmission. Each branch may itself bemade of one or more wires.

As discussed above, it may be valuable for the system to be able tocount the number of solar panels 102 connected to smart station 108.Herein follows embodiments of methodologies by which the count may beobtained for AC modules. Panels 102 as discussed herein may beconsidered AC modules (see, e.g., FIG. 7), but this need not be thecase.

One embodiment of a counting methodology is to utilize resistors inconjunction with each panel 102 and smart station 108. Referring now toFIG. 12, the layout will define a circuit with an internal resistance1204 within the smart station 108 and an external resistance 1202created by the network of solar panels 102 and related components. Anoptional additional resistance 1210 may also be provided internally orexternally to balance the overall performance, but for ease ofdiscussion in the embodiments herein the resistance is not present(zero) unless otherwise specified.

Resistances 1202 and 1206 (along with 1210 if present) act as a voltagedivider, such that an applied voltage +Vin will result in a reducevoltage +Vout. Since the number of panels 102 at least in partdetermines the external resistance 1202, the voltage output +Vout willbe different based on the number of panels 102. Smart station 108applies an algorithm or applies a data table to convert the +Vout into acorresponding number of panels 102, thereby counting the number ofpanels.

By way of general example for explanation purposes only, presumeresistance 1204 is 100 ohms, and the collective resistance 1202 fromthree (3) solar panels connected to smart station 108 is 100 ohms. If+Vin is 5 volts, then +Vout is 2.5 volts, assuming resistor 1210 has aresistance of 0 ohms. Smart station 108 determines by either formula orconsultation of a data table that 2.5 volts corresponds to a voltagethat would be expected for three connected solar panels 102 connection.Smart station 108 thus determines that three panels are present becauseit received 2.5 volts as +Vout, as opposed to some other number.

By way of comparison example, presume resistor 1204 is 100 ohms, and thecollective resistance 1202 from nine (9) solar panels connected to smartstation 108 is 300 ohms. If +Vin is 5 volts, then +Vout is 1.25 volts.Smart station 108 determines by either formula or consultation of a datatable that 1.25 volts corresponds to a voltage that would be expectedfor nine connected solar panels 102. Smart station 108 thus determinesthat nine panels are connected because it received 1.25 volts as +Vout,as opposed to some other number.

Practical implementation of the above methodologies relates toestablishing a paradigm and supporting architecture by which collectiveresistance 1202 is unique to the environment of solar panels 102. By wayof example, collective resistance 1202 should be sufficiently differentfor 3 connected solar panels relative to 4 connected solar panels suchthat smart station 108 can distinguish the corresponding +Vout outsideof a range of tolerance. Specifically, resistors and electricalcomponents have various tolerances, and the determination methodology ofsmart station 108 allows for variance. Thus, +Vout does not need to meetan exact value, but rather a value within a range of tolerance common tosuch components. (All discussion of meeting certain values as hereindescried or claimed is to be understood to allow for such variation,regardless of whether it is expressly stated). Ultimately, the +Vout forany particular connected number of panels and related components issufficiently unique and outside the range of tolerance of a differentenvironment that it can be recognized by smart station 108.

Currently, there are two predominant types of connections for panels102: daisy chain strings and trunk branch. Each may raise differentconsiderations in the implementation of the counting methodology.Preferably, these considerations are addressed via the cabling thatconnects industry standard solar panels; however, the invention is notso limited and the architecture can be based on custom panels and/orcables.

A daisy chain string often involves a parallel connection of the powerpathway for voltage generated by individual panels. Referring now toFIGS. 13A-C, a first common type of AC solar panel 1300 (which may bepanel 102 in the prior embodiments) is configured as daisy chain string,in which panels 1300 are connected in series by cables 1312. Such panels1300 may have a micro inverter 1302 with two power/data pathways1306/1308 and two end connectors 1308/1310. Panel 1300 includescapacitors and/or capacitive elements generically shown at 1350.

Cables 1312 with end connectors 1316 and 1318 connect smart station 108to the most upstream panel 1300 in the series, and each subsequent pairof panels 1300. An end cap 1314 closes off the last connector 1308 ofthe most downstream panel in the daisy chain string. With all componentsproperly connected an electrical path collectively runs from smartstation 108 through all panels 1300 to end cap 1314.

Cable 1312 includes at least 4 pathways, which are preferablyconductors. Pathways 1320 (L1) and 1322 (L2) collectively form theoverall pathway for power generated by the solar panels 102 to transmitto the smart station 108 for ultimate transmission to the home loadcenter 110. Pathway 1324 (S) is a signal pathway and preferably carriesa low voltage signal (e.g., 5 volts or less). Pathway 1326 (G) is areturn pathway that may combine with pathway 1324 to form a circuit toapply a signal in the form of an applied voltage. Return pathway 1326can also discharge current from a ground fault, although a separatepathway may be provided for that purpose. End connectors 1316 and 1318connect the cable 1312 to other cables and input/outputs as appropriate.FIG. 14 shows a panel 1300 connected upstream to a cable 1312 anddownstream to an end cap 1314.

FIG. 15 shows the embodiment of FIG. 13 configured to count the numberof panels 1300 and/or the presence of end cap 1314 with reference to thecorresponding signal pathway 1324 and return pathway 1326. A resistor R1is provided for each panel 1300 as a parallel circuit element betweenpathways 1324 and 1326; preferably each resistor R1 is identical, butthis need not be the case. A final resistor R2 is provided in parallelwith pathways 1324 and 1326 and downstream of the last panel 1300 in thesequence. Resistances R1 and R2 are preferably different, and moreparticular at least 15 times different. As discussed in more detailbelow, resistors R1 represent passive elements for each panel 1300,while resistor R2 is part of an end cap of the daisy chain string.

The combination of resistor R2 and as many R1s as may be present formthe collective resistance 1202, which can be calculated using standardequations as are known in the art. Based on the number of panels 1300and corresponding number of resistors R1 present, the voltage divider ofsmart station 108 will produce a particular output +Vout that smartstation 108 can convert into a panel count, such as by comparing theparticular +Vout to a data table of expected +Vout values.

The +Vout is thus different based on the number of connected panels1300. Since these values can be calculated in advance using standardcircuit equations, smart station 108 can be pre-loaded with data, suchas in a data table, matching various connection scenarios with theircorresponding calculated +Vout values; when a produced +Vout value isreceived by smart station 108, it compared the received +Vout with thestored expected +Vout values in the table to identify the correspondingsystem setup and number of modules. In this manner smart station 108counts/determines the number of solar panels 1300 connected in thestring. A non-limiting example of a table using the above-noted values(R1=39 k ohms, R2=2 k ohms, resistor 1206=1220 ohms, and +Vin=5.0 v) isas follows:

TABLE 1 # panels R w/cap V w/cap V min V max R w/o cap V w/o cap 13102.439 1.933962 1.912689 1.955236 40200 0.149254 2 3013.953 1.9907411.968843 2.012639 20700 0.289855 3 2933.333 2.045455 2.022955 2.06795514200 0.422535 4 2859.574 2.098214 2.075134 2.121295 10950 0.547945 52791.837 2.149123 2.125482 2.172763 9000 0.666667 6 2729.412 2.1982762.174095 2.222457 7700 0.779221 7 2671.698 2.245763 2.221059 2.2704666771.429 0.886076 8 2618.182 2.291667 2.266458 2.316875 6075 0.987654 92568.421 2.336066 2.310369 2.361762 5533.333 1.084337 10 2522.0342.379032 2.352863 2.405202 5100 1.176471 11 2478.689 2.420635 2.3940082.447262 4745.455 1.264368 12 2438.095 2.460938 2.433867 2.488008 44501.348315 13 2400 2.5 2.4725 2.5275 4200 1.428571 14 2364.179 2.5378792.509962 2.565795 3985.714 1.505376 15 2330.435 2.574627 2.5463062.602948 3800 1.578947 16 2298.592 2.610294 2.581581 2.639007 3637.51.649485 17 2268.493 2.644928 2.615833 2.674022 3494.118 1.717172 182240 2.678571 2.649107 2.708036 3366.667 1.782178 19 2212.987 2.7112682.681444 2.741092 3252.632 1.84466 20 2187.342 2.743056 2.7128822.773229 3150 1.904762

The first column of Table 1 represents the number of panels 1300, andeach row reflects data for that particular panel 1300. The second column“R w/cap” represents the expected collective resistance 1202 in ohms forthe particular number of panels 1300 in combination with a properlyinstalled end cap 1314. The third column “V w/cap” represents theexpected +Vout voltage for the particular number of panels 1410 incombination with a properly installed end cap 1314.

By way of non-limiting example, R1 can be 39 k ohms, R2 can be 2 k ohms,resistor 1206 can be 1220 ohms, and +Vin can be 5.0 v. If only one panel1300 is present, the +Vout is expected to be 1.933962 volts. If twopanels 1300 are present, then +Vout is expected to be 1.990741 volts. Iffive panels 1300 are present, then +Vout is expected to be 2.149123volts.

In practice, resistors and other circuit elements are not exact values,but rather have a tolerance and corresponding range of error. Atolerance of ±1% is a typical tolerance for resistors and is appropriatefor use with at least some embodiments herein, although the invention isnot limited to the same. Due to the tolerance, the +Vout of the systemwould not exactly match the voltages listed in the second column ofTable 1. Rather, the +Vout would be expected to fall within some rangearound those values. This range may be expressed by way of non-limitingexamples as ±value off the expected +Vout (e.g., ±1%). In anothernon-limiting example, the range can be specifically defined bycalculating the expected minimum and maximum voltages +Vout due to themost extreme state of tolerance (e.g., all resistors at +1% of tolerancev. all resistors at −1% of tolerance), such as shown in the fourth andfifth columns of the table. Smart station 108 thus compares the received+Vout from the voltage divider to the noted ranges to identify thecorresponding number of panels. In this context, all discussion of matchin +Vout as discussed herein includes allowance for this range oftolerance in both the specification and claims, regardless of whetherexpressly stated.

By way of non-limiting example, if the received +Vout is 2 volts, thenper Table 1 smart station 108 would determine that two (2) panels areconnected with properly installed end cap 1314 because 2 volts fallswithin the Vmin and Vmax for a two panel configuration with a properlyinstalled end cap 1314.

As discussed above, end cap 1314 closes off an electrical connection atthe far end of the daisy chain string; failure to include and properlyinstall the end cap may present a failure/safety hazard due to waterentering the electrical system. By incorporating resistor R2 into endcap 1314, the system can detect the proper/improper installation of endcap 1314. Specifically, the values of the second-fifth columns are basedon a properly connected end cap 1314 and the corresponding expectedcollective resistance 1202 and voltage +Vout. However, referring now toFIGS. 16A and B, if the end cap 1314 is not connected, then resistor R2is not connected, resulting in a different collective resistance 1202defined only by the parallel connections of the resistors R1. As thiscondition can be pre-calculated it may be line item in the data table toidentify a missing end cap 1314, and such values are reflected in thesixth and seventh columns of Table 1.

By way of non-limiting example, using the numbers above, a single panel1300 with an end cap 1314 would result in an expected +Vout of 1.933962,but a single panel 1300 with a missing end cap 1314 would result in a+Vout of approximately 0.149254. In the alternative, there may be nocorresponding voltage in the data table, in which case the system couldsimply respond through the interface with an error indicator. In eithercase, smart station 108 would disable the flow of power from the panels1300 until the error was corrected (which it would determine by asubsequent counting effort in which an appropriate +Vout is received).

The various resistor and voltage values that support and are set forthin Table 1 are exemplary only, and other combinations may be used. Thecombination selected may have certain features. One such feature is thatthe range of expected voltages for any one circumstance should notoverlap with the range for a different circumstance. For example, inTable 1 above, for one panel the Vmin/max is approximately 1.912-1.955volts, while for two panels the Vmin/max is approximately 1.969-2.012volts. Due to the lack of overlap, no +Vout would be received whichcould be attributed to different numbers of panels.

A second feature of the resistor combination is that the resistor valuesof R1 and R2 are so different that the entire range of voltages forpanels 1300 with end caps 1314 does not overlap with the entire range ofvoltages for panels 1300 without end caps 1314. In the example of Table1, the entire range of voltages for panels 1300 with end caps 1314 isapproximately 1.912 volts (1 panel, Vmin) to 2.712 volts (20 panels,Vmax), while the entire voltage range of for panels 1300 without endcaps 1314 is 0.149 to 1.904 volts. Due to the lack of overlap, no +Voutwould be received with a missing end cap 1314 which could be attributedto a configuration with an end cap present.

The same methodology can indicate whether there is a break in the daisychain string connection such that only some of the panels 1300 areconnected. Referring now to FIG. 17, a break in the cable 1312 generatesan electrical gap 1702; for purpose of illustration the break is betweenthe first and second panel 1300 closest to the smart station 108, butthe break may be anywhere along the pathways. The daisy chain stringconnection is open circuited by the gap 1702 such that no power can flowfrom panels 1300 at all. Yet +Vin does flow in the still connectedportions of pathways 1324 and 1326, for which the resulting +Vout wouldbe consistent with one (1) connected panel in combination with a missingend cap 1314. The absence of power in combination with a +Vout wouldallow controller to indicate that there is a break in the electricalpath between the first and second panels 1300 in sequence.

FIGS. 18A-C show different embodiments of how resistor R1 may beincorporated into the architecture of a daisy chain string. Resistor R1can be incorporated into panel 1300, such as by way of non-limitingexample incorporated into connector 1310 of panel 1300 in FIG. 18A, andthus provided by the solar panel manufacturer. In FIG. 18B, resistor R1is incorporated into connector 1316 of cable 1312, and can thus be partof the cable itself as provided by the cable manufacturer. In FIG. 18C,resistor R1 is incorporated into an intermediate connector 1802 that canbe inserted between connectors 1310 and 1316.

Resistor R2 can be similarly positioned relative to end cap 1314 in thethree embodiments of FIG. 18A-18C, i.e., within the panel 1300, the endcap 1314, or an intermediate component. Incorporation into the end cap1314 is the most preferable as shown in FIG. 19, as the presence orabsence of R2 would thus directly correlate to the presence or absenceof the end cap 1314 in the electrical pathway.

Referring now to FIGS. 20A-C, a trunk branch configuration is shown fora solar panel 2000. Solar panel 2000 include a micro inverter 2002connected to a connector 2010 via a cable 2006, as well as capacitorsand/or capacitive elements shown generically at 2050. A cable 2012connects at one end to smart controller 108. Connectors 2020 are placedalong the length of cable 2012 with a last connector 2022 at the distalend. As shown in FIG. 20B, the number of connectors 2020/2022 may equalthe number of panels 2000, and as such each such connector 2020/2022connects to a connector 2010 of panel 2000. However, as shown in FIG.20C, there may be fewer panels 2000 than connectors 2020/2022, in whichcase each unused connector 2020/2022 has a mounted end cap 2028.

In the series connection, the cabling that defined the electricalpathways comprises a series of individual cable segments that connectedeach component. The trunk branch connection may be made from a singlecable with branch connectors along its length.

Referring now to FIG. 21, cable 2012 preferably includes at least 4pathways, which are preferably conductors. Pathways 2102 (L1) and 2104(L2) form the overall pathway for utility power generated by the solarpanels 2000 to transmit to the smart station 108 for ultimatetransmission to the home load center 110; both pathways 2102 and 2104are in parallel with the panels 2000 and connected in a known manner notdiscussed further herein. Pathway 2106 is a signal pathway andpreferably carries a low voltage signal (e.g., 5 volts or less). Pathway2108 (G) is a return pathway that may combine with signal pathway 2106to form a circuit to apply a low voltage signal (e.g., 5 volts or less).Return pathway 2108 can also act as a pathway to discharge current froma ground fault. A resistor R3 is provided for each panel 2000 as aseries circuit element in signal pathway 2106; preferably each resistorR3 is identical, but this need not be the case. Resistors R3 representpassive elements for each panel 2000.

The combination of as many resistors R3 as may be present form thecollective resistance 1202, which can be calculated using standardequations as are known in the art. Based on the number of panels 2000and the corresponding number of resistors R3 present, along with anyresistances (e.g., 1204, 1210) or circuit elements the voltage dividerwill produce a particular output +Vout that smart station 108 canconvert into a module count, such as by comparing the particular +Voutto a data table of expected +Vout values.

The +Vout is thus different based on the number of connected panels1300. Since these values can be calculated in advance using standardcircuit equations, smart station 108 can be pre-loaded with data, suchas in a data table, matching various connection scenarios with theircorresponding calculated +Vout values; when a +Vout value is received bysmart station 108, it compared the received +Vout with the stored +Voutvalues in the table to identify the corresponding system setup andnumber of modules. In this manner, smart station 108 counts/determinesthe number of solar panels 102 connected in the string. A non-limitingexample of a table using the above-noted values (R3=330 ohms, resistance1206=100 ohms, resistance 1210=100 ohms and +Vin=5.0 v) is as follows:

TABLE 2 # panels V w/no open V min V max 1 3.113207547 3.1443396233.019811 2 2.619047619 2.645238095 2.540476 3 2.260273973 2.2828767122.192466 4 1.987951807 2.007831325 1.928313 5 1.774193548 1.7919354841.720968 6 1.601941748 1.617961165 1.553883 7 1.460176991 1.4747787611.416372 8 1.341463415 1.354878049 1.30122 9 1.240601504 1.2530075191.203383 10 1.153846154 1.165384615 1.119231 11 1.078431373 1.0892156861.046078 12 1.012269939 1.022392638 0.981902 13 0.953757225 0.9632947980.925145 14 0.901639344 0.910655738 0.87459 15 0.85492228 0.8634715030.829275 16 0.812807882 0.820935961 0.788424 17 0.774647887 0.7823943660.751408 18 0.739910314 0.747309417 0.717713

The first column of Table 2 represents the number of panels 2000, andeach row reflects data for that particular panel 2000. The second columnV with no open represents the expected +Vout voltage for the particularnumber of panels 200 in combination with any properly installed end caps2024. As discussed above with respect to series connections, the +Vout,of the system would not exactly match the voltages listed in the secondcolumn due to tolerances, and Vmin and Vmax may be provided to setexpected ranges of +Vout shown in the remaining columns (+1% and −3% inTable 2, although the invention is not so limited). Separate columns arenot needed to account for end caps, for as discussed below the absenceof end cap would generate an open circuit and +Vout would be zero.

The various resistor and voltage values that support and are set forthin Table 2 are exemplary only, and other combinations may be used. Thecombination selected may have certain features such as those discussedabove.

Referring now to FIG. 22, an embodiment of the internal architecture ofthe cabling and connectors are shown for the embodiment of FIG. 20B inwhich each connector 2022/2020 is connected with a corresponding panel2000. In this embodiment, cable 2012 is a 5 pole cable, including powerpathways 2012 and 2104, signal pathway 2106, return pathway 2108, and aneutral pathway 2202 (which is particular to the panel environment andmay otherwise not have any specific relevance to counting methodology;and may in fact be omitted entirely). The electrical pathways of powerpathways 2012 and 2104, return pathway 2108, and a neutral pathway 2202extend from beginning to end and connect to connector 2010 of panel 2000in parallel in a known manner.

The signal pathway 2106 extends in series from smart station 108 to thefirst connector 2020, ending at a first terminal 2204. Signal pathway2106 recommences from a second terminal 2206 in connector 2010 andcontinues downstream along the signal pathway 2106. Within connector2010, first terminal 2204 and second terminal 2206 preferably do notconnect, thereby forming an open circuit.

The connector 2010 of panel 2000 has a first terminal 2208 and a secondterminal 2210 that can mate with terminals 2204 and 2206 of connector2020. Resistor R3 is provided in series between first terminal 2208 anda second terminal 2210. When connectors 2010 and 2020 are connectedtogether, the resistor R3 bridges the terminals 2204 and 2206, therebyclosing the circuit pathway and contributing to the collectiveresistance 1202 as discussed above.

Signal pathway 2106 will from second terminal 2206 downstream along thenext segment of cable 2012, terminating at the first terminal 2204 ofthe next connector 2020. This configuration repeats for all of theconnectors 2020, up until the last connector 2022. Cable 2022 has afirst terminal 2212 for the signal pathway 2106 similar to firstterminal 2204 in connectors 2020. A second terminal 2214 is alsoprovided, but it connects back to the return pathway 2108.

FIG. 22 shows resistor R3 inside connector 2010 of the panel. Thisarrangement ensures that +Vout is only influenced in the presence of apanel 2000 and resistor R3 to count. However, other arrangements couldbe used. By way of non-limiting example, referring now to FIG. 23,resistor R3 could be in an intermediate connector 2302 that can beinserted between connectors 2010 and 2020, and each of connectors 2010and 2020 may have a different number of contacts to address thatenvironment (in this embodiment connector 2010 has 4 contacts, whileconnector 2020 has 6 contacts, although the invention is not solimited). Another example would be to place R3 in connector 2020 ofcable 2012, although as a practical matter this would potentiallyneutralize the ability to count the panels (R3 would indicate thepresence of a panel regardless of whether panel 2000 was connected).Another example would be to place resistor R3 somewhere else in panel2000.

As noted above, in a parallel configuration, not every connector2020/2022 needs be connected to a panel, and end cap 2024 closes off anelectrical connection of any unused connectors 2020/2022; failure toinclude and properly install the end cap may present a failure/safetyhazard due to water entering the electrical system. Referring now toFIG. 24, this is represented by an end cap 2024 being mounted on theshown connector 2022. The end cap has a wire pathway 2406 within end cap2024 to maintain the closed loop of signal pathway 2106 and returnpathway 2108. No resistor need be provided with end cap 2024 (whichdiffers from end cap 1314 in the series embodiment above).

By incorporating a bridging wire pathway 2406 into end cap 2024, thesystem can detect the proper/improper installation of end cap 2402.Specifically, if the end cap is missing, then the series pathway ofsignal pathway 2106 and return pathway 2108 will have a break 2502 asshown in FIG. 25. The open circuit will set +Vout at zero volts, whichsmart station 108 will interpret as an uncapped end of cable 2012.

The various resistors discussed above may be single or multipleresistors that collectively form a resistance as noted. Other circuitelements other then resistors may also be present, and in theory mayform part of the voltage divider.

While the above embodiments are based on counting panels via a voltagedivider, counting may also be based on capacitance. Specifically, eachpanel 102/1300/2000 has capacitors that provide clean power. Thecapacitance of the panels is a known/calculable quantity, and as suchthe initial current draw of each panel is a known/calculable quantity. Amethodology for counting panels according to an embedment of theinvention is to leverage this capacitive current draw to count thenumber of panels.

Referring now to FIG. 26, the capacitive methodology commences at aninitialization 2602, at which time the panels have been inactive suchthat any capacitors therein have discharged. At 2604 smart station 108applies utility power in reverse from the home load center 110 to thepanels. At 2606 the capacitors in the panels draw a current and begin tocharge. At 2608 smart station 108 determines the amount of currentneeded to charge the capacitors. At 2610, smart station 108 calculatesthe number of connected panels by a table or formula that applies theknown current draw per panel and the total current draw. A none limitingexample of such a formula is:

Number of panels=total current draw/known current draw per panel

The resistance and capacitive counting methodologies may have relativeadvantages and disadvantages. Both are highly accurate countingmethodologies and can be used separately. The resistance basedmethodology calls for supporting cabling and/or panel architecture asdiscussed herein, whereas a capacitance based methodology could operatewith conventional panels and cabling. The resistance based methodologycan be implemented before utility power is even connected and can be runduring installation or at any time after installation (e.g., offinternal power), whereas the capacitive methodology if preferably runwhen the panels are attached to utility power and the capacitors aredischarged (e.g., at night). Since a feature of embodiments of theinvention is to count panels as part of the installation process (e.g.,before utility power is connected), the resistance methodology is moreconducive for the same compared to the capacitive methodology. Bothmethodologies may be employed, in which case the smart controller candisable power if the two methodologies produce different panel counts.

Smart station 108 may be informed in advance of the number of panels 102that will or should be connected to it. Smart station 108 can comparethis number against the detected number, and inform the installer of adiscrepancy. Smart station 108 could also disable the flow of power fromthe panels 102 until the discrepancy was resolved.

Referring now to FIG. 27, an embodiment of a startup method for smartstation 108 is shown. At 2702 the various panels are connected and smartstation 108 is engaged. At 2704 various pre-utility power checks areconducted to confirm system parameters are within tolerable limits, suchas temperature, voltage, frequency, absence of ground fault, etc. If thesystem fails any such test than error protocols (e.g., notify theinstaller) are initiated at 2714. If all system checks are clear, thenumber of panels is counted at 2706. If the count indicates a problem(e.g., too many panels for system to handle, mismatch with pre-enterednumber of panels, missing end cap, break in electrical pathway), thenerror protocols at 2714 are initiated. In the absence of a problem, thenumber of panels is counted by the capacitive current draw method at2708. Error protocols are initiated if the counts do not match,otherwise the smart station 10 enables power at 2710 and allows thesystem to operate. Once in operation, smart station 108 willperiodically conduct various system checks, including but not limited toany or all of the checks described in connection with FIG. 27; failureof any system check may result in smart station 108 disabling the flowof utility power as described herein. The invention is not limited tothe order of FIG. 27, as the steps can be juxtaposed in whole or inpart.

Referring now to FIG. 28, another embodiment of the invention is shown,in this case an embodiment of a daisy chain connection of modules 2800in which the power from the modules are provided in series. Thesupporting architecture and counting methodology is consistent with thatdescribed with respect to FIGS. 13-19, and in particular FIG. 19 inwhich the resistor R1 is located within the module 2800 and resistor R2in which and for which like numerals represent like components. The twopower pathways L1 and L2 in FIGS. 13-19 are shown in FIG. 28 as AC+ andAC return. Each module 2800 has an AC+ and AC− terminal connected inseries, which in turn connects to the AC return line through end cap1414 to define the closed circuit power pathway.

Referring now to FIG. 29, another embodiment of the invention is shown,in this case an embodiment of a daisy chain connection of modules 2900in which the power from the modules are provided in a series circuit.The supporting architecture and counting methodology is consistent withthat described with respect to FIGS. 13-19 and in particular FIG. 19 inwhich the resistor R1 is located within the module 2900, and for whichlike numerals represent like components. The two power pathways L1 andL2 provide parallel pathways for receiving power from modules 2900,although they are not connected by end cap 1414.

The number of connected panels 2800/2900 is counted in the same manneras discussed above with respect to FIGS. 13-19, and the various resistorvalues discussed with reference to Table 1 may be used in theseembodiments, although the invention is not limited thereto. Breaks inthe cable and/or a missing end cap are similarly detected as discussedabove.

Referring now to FIG. 30, another embodiment of the invention is shown,in this case an embodiment of a trunk branch connection of modules 3000connected electrically in series, each via a connector 3010 and a cable3006. A cable 3012 connects at one end to smart controller 108.Connectors 3020 are placed along the length of cable 3012 with a lastconnector 3022 at the distal end that provides the option to connectadditional segments of cable 3012 (e.g., two segments of cable 3012 with5 connectors 3020 each to support 5 modules 3000 can connect togethervia connector 3022 to form a 10 connector cable 3012). Last connector3022 has a different shape than connector 3020 such that it would onlyconnect with another segment of cable 3012 and not accidentally connectwith a module 3000.

Cable 3012 preferably includes at least 4 pathways, which are preferablyconductors. Pathways 3102 (AC+) and 3104 (AC return) form the overallpathway for utility power generated by the solar panels 3000 to transmitto the smart station 108 for ultimate transmission to the home loadcenter 110; both pathways 3102 and 3104 are in series with the panels3000 and connected in a known manner not discussed further herein.Pathway 3106 (sensor) is a signal pathway and preferably carries a lowvoltage signal (e.g., 5 volts or less). Pathway 3108 (ground) is areturn pathway that may combine with signal pathway 3106 to form acircuit to apply a low voltage signal (e.g., 5 volts or less). Returnpathway 3108 can also act as a pathway to discharge current from aground fault.

A resistor R1 is provided for each panel 3000 and a resistor R2 isprovides in each end of line cap 3028 as a series circuit element insignal pathway 3106. A resistor R1 is provided for each panel 3000 as aparallel circuit element between pathways 3106 and 3108; preferably eachresistor R1 is identical, but this need not be the case. A resistor R2is provided in parallel with pathways 3106 and 3108 within each end ofline cap 3028 as may be present. Resistances R1 and R2 are preferablydifferent, and more particular at least 15 times different.

As discussed herein, the number of connectors 3020 may equal the numberof panels 3000, and if there are fewer panels 3000 than connectors 3020then each unused connector 3020 has a mounted end cap (not shown in FIG.30) such as discussed in other embodiments herein. The absence of an endcap would leave an open circuit is the series power pathway, such thatat least the lack of power flow would indicate an uncapped/unconnectedconnector 3020. Preferably such an end cap would provide an internalpathway from the AC+ to the AC− terminal to preserve the series powerpathway (similar to end cap 2024 discussed above). For countingpurposes, the end cap could also have no connection between the groundand sensor pathway similar to end cap 2024, or bridge the two pathwayswith a resistor similar to end cap 1414.

In the embodiments of FIGS. 28-29, the combination of resistor R2 and asmany R1s as may be present form the collective resistance 1202, whichcan be calculated using standard equations as are known in the art.Based on the number of panels 3000 and corresponding number of resistorsR1 present, the voltage divider of smart station 108 will produce aparticular output +Vout that smart station 108 can convert into a panelcount, such as by comparing the particular +Vout to a data table ofexpected +Vout values. The resistor values used in connection with Table1 would yield the same results for the embodiments of FIGS. 28 and 29.

The embodiment of FIG. 30 would yield similar results for all connectors3022 of the trunk occupied by modules 3000 and end of line connector3022 capped by end of line cap 3028, although as noted above there maybe additional combinations to account for end caps of missing panels.Consistent with other embodiments, resistor values selected for thatenvironment would establish non-overlapping ranges of expected +Voutfrom the voltage divider such that a particular combination ofpanels/end caps could be identified from the resulting +Vout.

Several of the above counting methodologies are specific to series orparallel connections of panels, be it daisy chain or trunk cable.However, the invention is not so limited, and hybrids may also by, e.g.,leveraging a balance of the various resistances to generate particular+Vout that is discernible to particular combination/layout of panels andrelated components.

Various embodiments herein relate to daisy chain and truck branchsystems. However, the invention is not so limited, and other systems maybe used.

Several of the above methodologies disclose counting the number ofpanels along a particular electrical pathway. As shown for example inFIG. 1, there may be multiple pathways. The embodiments herein may countthe panels on the individual pathways and combine the data to apply asdictated by other needs of the system.

The specification and drawings are, accordingly, to be regarded in anillustrative rather than a restrictive sense. It will, however, beevident that various modifications and changes may be made thereuntowithout departing from the broader spirit and scope of the invention asset forth in the claims.

1-11. (canceled)
 12. A controller for a solar panel system for how manysolar panels are connected to the controller, comprising; an interfaceconnectable an electrical pathway connecting the controller to thenumber of solar panels, each of the solar panels having a firstresistance; a second resistance associated with the controller, thesecond resistance defining at least a portion of a voltage divider; thecontroller being programmed to: apply an input voltage to the voltagedivider; receive an output voltage from the voltage divider; determinefrom the output voltage the number of solar panels connected to thecontroller by the electrical pathway; wherein when the interface isconnected by the electrical pathway to the number of solar panels, acollective resistance of the first resistance of each of the number ofsolar panels partially defines the voltage divider such that the outputvoltage varies based on how many solar panels are connected.
 13. Thecontroller of claim 12, further comprising: a data table listing variouspredicted output voltages of the voltage divider and corresponding knownconfigurations of solar panels; and the controller being programmed todetermine from the produced output voltage the total number of the atleast one solar panel connected to the controller comprising matchingthe produced output voltage to a predicted output voltage from the tableto identify a matching number of panels.
 14. The controller of claim 12,wherein the controller is programmed to determine an unconnectedconnector in the electrical pathway based on at least the producedoutput voltage.
 15. The controller of claim 12, wherein the controlleris programmed to determine a location in the electrical pathway of anunconnected connector based on at least the produced output voltage. 16.The system of claim 12, further comprising: the controller beingprogrammed to be aware of an independently derived count of the totalnumber of the at least one solar panel; the controller being programmedto disable flow of utility power in response to the second count beingdifferent than the total number of panels determined from the producedoutput voltage.
 17. A solar panel system, comprising: a plurality ofsolar panels, each panel having an associated passive element that isconfigured to modulate a signal, each panel configured to generateutility power and to transmit information including the signal asmodulated by the passive element, the information being distinct fromthe utility power; an input connector, configured to receive the powerfrom the solar panels and the information from the solar panels; anoutput, configured to forward the utility power from the solar panelsfor end consumption; a cable configured to connect to the plurality ofsolar panels and the input connector, and having a power pathway forpassing the power to the input connector, and having a data pathwaydistinct from the power pathway, for passing the information to theinput connector; the controller comprising hardware in combination withsoftware, the controller being programmed to: first determine the totalnumber of solar panels electrically connected to the input connectorfrom modulated signals in the information received at the inputconnector; second determine whether the total number of solar panelsexceeds a predetermined threshold; enable the flow of power to theoutput in response to at least the total number of the solar panelscounted by the controller is determined by the controller to be within afirst threshold; and disable the flow of power in response to the totalnumber of the solar panels counted by the controller is determined bythe controller to exceed the first threshold.
 18. The system of claim17, wherein the passive element is a resistor.